The present invention relates to a hair dye composition which has markedly high dyeing power, can impart the hair with a remarkably vivid color ranging from red to blue, has less color fade over time and undergoes a small color tone change in the dye even after storage.
Hair dyes can be classified by the dye to be used therefor, or whether they have bleaching action of melanin or not. Typical examples include a two-part permanent hair dye composed of a first part containing an alkali agent, an oxidation dye and a direct dye such as nitro dye and a second part containing an oxidizing agent; and one-part semi-permanent hair dye containing an organic acid or an alkali agent, and a direct dye such as acid dye, basic dye or nitro dye.
The above-described permanent hair dye is however accompanied with the drawbacks that color tone imparted by an oxidation dye is not so vivid and the color of the hair dyed with a vivid-color producing nitro dye ordinarily employed as a direct dye markedly fades over time and becomes dull soon even if the color tone rightly after dyeing is very vivid (Japanese Patent Application Laid-Open (Kokai) No. Hei 6-271435).
Recently, hair dyes containing as a direct dye a so-called cationic dye having a cation group contained in their conjugate system have been reported (Japanese Language Laid-Open Publication (PCT) No. Hei 8-507545, 8-501322 or 10-502946, or Japanese Patent Application Laid-Open (Kokai) No. Hei 10-194942). They have however been found to involve drawbacks that intended dyeing effects are not available owing to decomposition of them caused by mixing, upon hair dyeing, with hydrogen peroxide ordinarily employed as an oxidizing agent; and that when the cation group is incorporated in an azo(xe2x80x94Nxe2x95x90N)-based conjugated system, they are unstable to an alkali agent or a reducing agent essentially contained in a permanent hair dye.
An object of the present invention is to provide a hair dye composition featuring high hair dyeing power, less color fade over time and excellent storage stability not permitting a large color tone change of the dye after storage.
The present inventors have found that a hair dye composition containing the below-described compoundxe2x80x94which is known as a dye for dyeing or printing therewith fiber materials, paper or leather and is, for example, described in Japanese Patent Application Laid-Open (Kokai) No. Sho 47-9107, Japanese Patent Application Laid-Open (Kokai) No. Sho 49-108378, Japanese Patent Application Laid-Open (Kokai) No. Sho 51-8317, Japanese Patent Application Laid-Open (Kokai) No. Sho 53-27626, Japanese Patent Application Laid-Open (Kokai) No. Sho 53-27627, Japanese Patent Application Laid-Open (Kokai) No. Sho 55-135169, Japanese Patent Application Laid-Open (Kokai) No. Sho 63-135458, German Patentschrift DE 1569660, or Japanese Patent Application Laid-Open (Kokai) No. Sho 58-103561xe2x80x94can dye the hair with high dyeing power without causing decomposition of the dye upon hair dying, can strongly impart the hair with a markedly vivid color ranging from red to blue, exhibits excellent light resistance, washing resistance, perspiration resistance, friction resistance and weather resistance, and undergoes a smaller change in color tone of the dye after storage as compared with that rightly after preparation because the dye exists in the composition stably.
In one aspect of the present invention, there is thus provided a hair dye composition comprising, as a direct dye, a compound represented by the following formula (1), (2), (3) or (4): 
[wherein, R1 and R1xe2x80x2 each independently represents a C1-6 alkyl group which may have a substituent or an aryl group which may have a substituent;
W and Wxe2x80x2 each independently represents a group xe2x80x94Axe2x80x94NR2R3 or a heterocyclic aromatic group which may have a substituent;
A and Axe2x80x2 each independently represents a divalent aryl group which may have a substituent;
R2, R2xe2x80x2 and R3 each independently represents a hydrogen atom, a C1-6 alkyl group which may have a substituent or an aryl group which may have a substituent; or R2, R2xe2x80x2 or R3 may be bonded to A or Axe2x80x2, thereby forming a nitrogen-containing heterocycle, R2 and R3 are coupled to form a nitrogen-containing heterocycle, together with the adjacent nitrogen atom, or R2 and R2xe2x80x2 are coupled to form a nitrogen-containing heterocycle together with the adjacent two nitrogen atoms and Q;
R4, R5 and R6 each independently represents a hydrogen atom, a C1-6 alkyl group which may have a substituent or C2-6 alkenyl group which may have a substituent;
Q represents a divalent organic connecting group;
X represents a modified carboxy group, an xe2x80x94SO2xe2x80x94Txe2x80x94 group (in which, T represents a C1-4 alkyl group, C2-4 alkenyl group or an aryl group) or a heterocyclic group;
Y represents a cyano group or a heterocyclic group;
Z represents a cationic group,
rings b, c, B, C, Bxe2x80x2 and Cxe2x80x2 each independently may have a substituent other than that described directly in the formula, or when in the formula (1), R1 represents a C1-6 alkyl group and W represents a group xe2x80x94Axe2x80x94NR2R3 (except that R2 or R3 is coupled with A to form a nitrogen-containing heterocycle), any one of the rings b, c and A has at least one substituent; and
Anxe2x88x92 represents an anion).
In another aspect of the present invention, there is also provided a hair dyeing method which comprises appying the above-described hair dye composition to the hair.
In the formulas (1) to (4), examples of the C1-6 alkyl group as R1, R1xe2x80x2, R2, R2xe2x80x2, R3, R4, R5 or R6 include methyl, ethyl, propyl, isopropyl and cyclohexyl groups, which may each be substituted by an aryl, alkoxy, amino, hydroxyl or cyano group, or a halogen atom.
In the formulas (1), (2) and (4), examples of the aryl group as R1, R1xe2x80x2, R2, R2xe2x80x2 or R3 include phenyl and naphthyl groups, which may each be substituted by an alkyl, aryl, alkoxy, amino, dialkylamino, hydroxyl, cyano or nitro group, of a halogen atom, more specifically, methyl, ethyl, methoxy, ethoxy or diethylamino group, or a chlorine or bromine atom.
In the formulas (3) and (4), examples of the C2-6 alkenyl group as R4, R5 or R6 include ethenyl and propenyl groups, which may each be substituted by a cyano or phenyl group.
In the formulas (1), (2) and (4), examples of the divalent aryl group as A or Axe2x80x2 include phenylene and naphthylene groups. In the formulas (1) and (4), examples of the heterocyclic aromatic group as W or Wxe2x80x2 include indolyl, particularly 3-indolyl group, which may be substituted by an alkyl, aryl, alkoxy, amino, hydroxyl, cyano or nitro group, or a halogen atom, more specifically, a methyl, ethyl, methoxy or ethoxy group, or a chlorine or bromine atom.
In the formula (2), the below-described groups can be mentioned as examples of the divalent organic connecting group represented by Q. 
In the formula (3), examples of the modified carboxy group as X include cyano, alkylcarbamoyl and acyl groups.
In the formula (3), examples of the heterocyclic group as X or Y include the following groups: 
In the formula (3), examples of the cationic group as Z include trialkylammoniumyl groups such as trimethylammnoiumyl and triethylammoniumyl, pyridyl group and alkylcarbamoyl groups having these groups bonded thereto.
In the formulas (1) to (4), examples of the substituent for the rings b, c, B, C, Bxe2x80x2 or Cxe2x80x2 include alkyl, alkenyl, aryl, alkoxy, amino and carbamoyl groups which may each have a substituent, hydroxyl group, cyano group, nitro group and halogen atoms. Specific examples include methyl group, ethyl group, methoxy group, ethoxy group, chlorine atom, bromine atom, dimethylamino group, N,N-diethylcarbamoyl group, piperidinocarbonyl group, cyanoethenyl group, cyanopropenyl group and ethylsulfonylethenyl group.
In the formulas (1) to (4), examples of the anion represented by Anxe2x88x92 include chloride ions, bromide ions, iodide ions, trichlorozincic acid ions, tetrachlorozincic acid ions, sulfuric acid ions, hydrogensulfuric acid ions, methyl sulfate ions, phosphoric acid ions, formic acid ions and acetic acid ions.
The following are specific examples of the direct dyes (1) to (4) to be used in the present invention: 
As the direct dyes (1) to (4), one or more can be used. Alternatively, another direct dye can be used in combination. The combination of the direct dye of the present invention with red and blue dyes makes it possible to dye the hair with a deep and highly lustrous dark brown or black color.
Examples of the direct dye other than the direct dyes (1) to (4) include Basic Blue 7 (C.I. 42595), Basic Blue 26 (C.I. 44045), Basic Blue 99 (C.I. 56059), Basic Violet 10 (C.I. 45170), Basic Violet 14 (C.I. 42515), Basic Brown 16 (C.I. 12250), Basic Brown 17 (C.I. 12251), Basic Red 2 (C.I. 50240), Basic Red 22 (C.I. 11055), Basic Red 76 (C.I. 12245), Basic Red 118 (C.I. 12251:1) and Basic Yellow 57(C.I. 12719); and basic dyes as described in Japanese Patent Publication No. Sho 58-2204, Japanese Patent Application Laid-Open No. Hei 9-118832, Japanese Language Laid-Open Publication (PCT) No. Hei 8-501322 or Japanese Language Laid-Open Publication (PCT) No. Hei 8-507545.
The direct dyes (1) to (4) are each preferably added in an amount of 0.01 to 20 wt. %, more preferably 0.05 to 10 wt. %, especially 0.1 to 5 wt. % based on the whole composition (after mixing of all the parts when a two-part or three-part composition is employed; this will apply equally hereinafter). When another direct dye is used in combination, the content of it in total with the direct dye of the present invention preferably ranges from 0.05 to 10 wt. %, especially 0.1 to 5 wt. % based on the whole composition.
The hair dye composition of the present invention is preferably adjusted to pH 6 to 11, with pH 8 to 11 being more preferred. Examples of the alkali agent to be used for pH adjustment include ordinarily employed ones such as ammonia, organic amines and salts thereof. The alkali agent is preferably added in an amount of 0.01 to 20 wt. %, more preferably 0.1 to 10 wt. %, especially 0.5 to 5 wt. % based on the whole composition.
In the hair dye composition of the present invention, an oxidizing agent can be incorporated. In this case, hair dyeing and bleaching can be carried out simultaneously, which facilitates more vivid hair dyeing. Ordinarily employed oxidizing agents, for example, hydrogen peroxide, persulfates such as ammonium persulfate, potassium persulfate and sodium persulfate, perborates such as sodium perborate, percarbonates such as sodium percarbonate and bromates such as sodium bromate and potassium bromate are usable. Out of them, hydrogen peroxide is especially preferred. The oxidizing agent is added in an amount of 0.5 to 10 wt. %, especially 1 to 8 wt. % based on the whole composition.
In the hair dye composition of the present invention, an oxidation dye can be incorporated further. In this case, this incorporation enables remarkably vivid dyeing not attainable by the single use of an oxidation dye. As the oxidizing agent, the above-exemplified ones can be used, with hydrogen peroxide being particularly preferred. Alternatively, an oxidizing enzyme such as laccase can be employed. As the oxidation dye, known developers and couplers ordinarily employed for an oxidation type hair dye can be used.
Examples of the developer include p-phenylenediamines having one or several groups selected from NH2xe2x80x94, NHRxe2x80x94 and NR2-groups (in which, R represents a C1-4 alkyl or hydroxyalkyl group) such as p-phenylenediamine, p-toluylenediamine, N-methyl-p-phenylenediamine, chloro-p-phenylenediamine, 2-(2xe2x80x2-hydroxyethylamino)-5-aminotoluene, N,N-bis-(2-hydroxyethyl)-p-phenylenediamine, 2-hydroxyethyl-p-phenylenediamine, 2,6-dimethyl-p-phenylenediamine, methoxy-p-phenylenediamine, 2,6-dichloro-p-phenylenediamine, 2-chloro-6-methyl-p-phenylenediamine, 6-methoxy-3-methyl-p-phenylenediamine, 2,5-diaminoanisole, N-(2-hydroxypropyl)-p-phenylenediamine and N-2-methoxyethyl-p-phenylenediamine; 2,5-diaminopyridine derivatives and 4,5-diaminopyrazole derivatives; p-aminophenols such as p-aminophenol, 2-methyl-4-aminophenol, N-methyl-p-aminophenol, 3-methyl-4-aminophenol, 2,6-dimethyl-4-aminophenol, 3,5-dimethyl-4-aminophenol, 2,3-dimethyl-4-aminophenol and 2,5-dimethyl-4-aminophenol; o-aminophenols, o-phenylenediamines, 4,4xe2x80x2-diaminophenylamine and hydroxypropylbis(N-hydroxyethyl-p-phenylenediamine); and salts thereof.
Examples of the coupler include 1-naphthol, 1,5-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 5-amino-2-methylphenol, 5-(2xe2x80x2-hydroxyethylamino)-2-methylphenol, 2,4-diaminoanisole, m-toluylenediamine, resorcin, m-plenylenediamine, m-aminophenol, 4-chlororesorcin, 2-methylresorcin, 2,4-diaminophenoxyethanol, 2,6-diaminopyridine, 2-amino-3-hydroxypyridine, 4-hydroxyindole, 6-hydroxyindole, 2,4-diamino-6-hydroxypyrimidine, 2,4,6-triaminopyrimidine, 2-amino-4,6-dihydroxypyrimidine, 4-amino-2,6-dihydroxypyrimidine, 4,6-diamino-2-hydroxypyrimidine and 1,3-bis(2,4-diaminophenoxy)propane; and salts thereof.
As each of the developer and coupler, one or more can be used. Although no particular limitation is imposed on the content of the developer or coupler, it is preferably added in an amount of 0.01 to 20 wt. %, especially 0.5 to 10 wt. % based on the whole composition.
To the hair dye composition of the present invention, a known autoxidation dye typified by an indole or an indoline, or a known direct dye such as a nitro dye or a disperse dye can also be added.
When an anionic component (such as anionic surfactant or anionic polymer) is added to the hair dye composition of the present invention, it is preferred to satisfy the following equation:
xe2x80x9cIon activity concentration of the anionic component/ion activity concentration of the cationic direct dye (1), (2), (3) or (4)xe2x89xa68xe2x80x9d
The term xe2x80x9cion activity concentrationxe2x80x9d as used herein means xe2x80x9cmolar concentrationxc3x97ionic valencexe2x80x9d
Addition of a polyol, polyol alkyl ether, cationic or amphoteric polymer or silicone to the hair dye composition of the present invention is preferred for bringing about uniform hair dyeing effects and improvement in cosmetic effects.
In addition to the above-described components, those ordinarily employed as a raw material for cosmetics can be added to the hair dye composition of the present invention. Examples of such an optional component include hydrocarbons, animal or vegetable fats and oils, higher fatty acids, organic solvents, penetration promoters, cationic surfactants, natural or synthetic polymers, higher alcohols, ethers, amphoteric surfactants, nonionic surfactants, protein derivatives, amino acids, antiseptics, chelating agents, stabilizing agents, antioxidants, plant extracts, crude drug extracts, vitamins, colorants, perfumes and ultraviolet absorbers.
The hair dye composition of the present invention can be prepared in a conventional manner into a one-part composition, a two-part composition having a first-part component containing an alkali agent and a second-part component containing an oxidizing agent or a three-part composition having, in addition to these two components, a powdery oxidizing agent such as persulfate. The direct dyes (1), (2), (3) and (4) can each be incorporated in either one or both of the part components of the two-part or three-part composition. The one-part type is applied to the hair directly, while the two- or three-part type is applied to the hair after mixing the components upon hair dyeing.
No particular limitation is imposed on the form of the hair dye composition of the present invention. Examples include powder, transparent, liquid, emulsion, cream, gel, paste, aerosol, and aerosol foam. It preferably has a viscosity of 2000 to 100000 mPa.s when it is applied to the hair (after mixing of all the components when a two-part or three-part type composition is employed).